This project is directed toward the development of mathematical models for the allocation of high cost regional services, primarily emergency medical services. Prior work has included models for estimating demand for emergency transportation services and evaluating the effectiveness of expenditures for cardiac emergencies. In conjunction with the modeling activites, extensive data systems have been developed and are now being funded permanently by outside community sources. Current studies in progress include: 1) Emergency Facilities Categorization and the Regional Allocation of Emergency Medical Services, 2) Performance Measures for Emergency Medical Services Transportation, 3) The Interface of Ambulatory and Emergency Care, and 4) Allocation of EMS Resources Among a Small Group of Hospitals.